Improvement in girders for iron bridges



C. W. WHEELER.

Girders for Iron Bridges.

No.149,965, Pate`nted"Apri|2l,1874-.

WITNESSES: INVENTUB (f. wffyf @Wwf-M X n BY M ATTUBNEYS.

UNITED STATES PATENT OFFICE.

OYRUS W. WHEELER, OF BROWNSVILLE, NEBRASKA.

lVPRVNiNT IN GIFRS FOR IRON BRIDG'ES.

Specification forming part of Letters Patent No. 149,965, dated April 21, 1874; application led February 28, 1874.

To all whom it may concer-n:

Be it known that I, CYRUS W. WHEELER, of Brownsville, in the county of Nemaha and State of Nebraska, have invented a new and Improved Tubular Girder for Arch and Truss Bridges, of which the following is a specification:

In the accompanying drawing, Figure 1 represents a side view, and Fig. 2 a vertical transverse section on the line c c, Fig. l, of my iinproved girder for arch and truss bridges.

Similar letters of reference indicate correspondin g parts. v

The object of my invention is to construct girders for arch and truss bridges, which require, on account ot' their simplicit5T of construction, less riveting, and may, therefore, be manufactured at cheaper rates, combining therewith symmetrical appearance and great strength, without being weakened by the tension and counter rods passing through the same. My invention consists of a tubular girder produced of two quadrantal flanged sections, riveted to a longitudinal strengthening-piece and connected by a stiiening-chord, and a quadrantal lower section of wroughtiron.

-In the drawing, A represents the upper quadrantal sections of rolled iron, each section being somewhat larger than the arc of an angle of ninety degrees, and provided with tlanges a, extending under right angles therefrom. The upper langes a of section A are riveted to an intermediate piece of iron, b, oi' rectangular shape, equal in height to the ilanges, so that a slightly-attened semicircular tube is produced. The lower anges a are riveted to chord or diaphragm B, which forms the lateral connection of the girder, and also to the flanges d of the lower quadrantal see tion C. The chord or diaphragm B is made of rolled plate or latticed iron, and intended to give lateral strength to the girder and prevent the upper and lower sections from spreading. The lower section C is also of rolled iron, constructed with a radius equal to the chord of one of the upper sections A, and with flanges d extending parallel to chord B, and fitting exactly to it. rlhe lower section also connects the upper section, and gives additional lateral and vertical strength to the girder. The dat circular shape of the girder produces the nearly-square abutting of the iian ges, and reduces thereby the cutting or shearing strain on the rivets, which is a main objection in girders of quadrangular cross-section. rlhe intermediate piece b admits the passage ot' tension and counter rods in an arch-bridge, without cutting and weakening the anges. A tubular girder of great strength is thereby obtained, which requires less material and riveting, and may with advantage be used in the various constructions ot' arch and truss bridges.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- A tubular girder for arch and truss bridges, consisting of two upper {lan-ged quadrantal sections, riveted to a longitudinal strengthening-piece and to a lateral connecting chord or diaphragm, and a lianged lower section ot' quadrantal shape, constructed substantialhT as and for the purpose described.

CYRUS lV. YVHEELER.

IVitnesscs:

FRANK D. MUTE, H. E. GATES, WILLIAM H. HOOVER. 

